Control system and method for controlling an operational mode of a vehicle via multiple clutch assemblies

ABSTRACT

A first clutch assembly has an active state for transmitting rotational energy and an inactive state for not transmitting rotational energy. A generator has a generator shaft associated with the first clutch assembly. A second clutch assembly has an active state for transmitting rotational energy and an inactive state for not transmitting rotational energy. A transmission has a transmission shaft directly or indirectly associated with the second clutch assembly. A third clutch assembly has an active state for transmitting rotational energy and an inactive state for not transmitting rotational energy. An engine has an engine shaft associated with the third clutch assembly. A controller establishes an operational mode of the vehicle by controlling the states of the first clutch assembly, the second clutch assembly, and the third clutch assembly.

FIELD OF THE INVENTION

This invention relates to a control system for a vehicle and a methodfor controlling an operational mode of a vehicle via multiple clutchassemblies.

BACKGROUND OF THE INVENTION

In a series hybrid configuration, a hybrid vehicle may have an internalcombustion engine for providing rotational energy to a generator. Inturn, the generator converts the rotational energy into electricalenergy for one or more drive motors to propel the vehicle. In a parallelhybrid configuration, both the internal combustion engine and anelectric drive motor may apply rotational energy to one or more wheels(or tracks associated with wheels) to propel the vehicle. Thus, there isa need to have a single vehicle that can operate in the series hybridconfiguration or the parallel hybrid configuration.

SUMMARY OF THE INVENTION

A control system for a vehicle and a method for controlling theoperational mode of a vehicle comprise a group of clutch assemblies. Afirst clutch assembly has an active state for transmitting rotationalenergy and an inactive state for not transmitting rotational energy. Agenerator has a generator shaft associated with the first clutchassembly. A second clutch assembly has an active state for transmittingrotational energy and an inactive state for not transmitting rotationalenergy. A transmission has a transmission shaft directly or indirectlyassociated with the second clutch assembly. A third clutch assembly hasan active state for transmitting rotational energy and an inactive statefor not transmitting rotational energy. An engine has an engine shaftassociated with the third clutch assembly. A controller establishes anoperational mode of the vehicle by controlling the states of the firstclutch assembly, the second clutch assembly, and the third clutchassembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a first embodiment of a control system for avehicle.

FIG. 2 is a diagram of a second embodiment of a control system for avehicle.

FIG. 3 is a diagram of a third embodiment of a control system for avehicle.

FIG. 4 is a diagram of a fourth embodiment of a control system for avehicle.

FIG. 5 is a flow chart of a method for controlling the control system.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In accordance with one embodiment, FIG. 1 shows a control system 11 fora vehicle having multiple clutch assemblies (16, 26, and 34). Thecontrol system 11 comprises a first clutch assembly 16 associated with agenerator shaft 12 of a generator 10. A second clutch assembly 34 isassociated directly or indirectly with a transmission shaft 42 of atransmission 30. A third clutch assembly 26 is associated with an engineshaft 24 (e.g., crankshaft) of an engine 28. The first clutch assembly16, the second clutch assembly 34, and third clutch assembly 26 haveelectrical, optical, or databus connections to a controller 75. In oneembodiment, the first clutch assembly 16, the second clutch assembly 34,and the third clutch assembly 26 each comprise electromagnetic clutches.The controller 75 establishes an operational mode of the vehicle bycontrolling the states of the first clutch assembly 16, the secondclutch assembly 34, and the third clutch assembly 26 via one or morecontrol signals.

A user interface 77 is coupled to the controller 75 for providing useror operator input to the controller 75. The user interface 77 maycomprise a switch (e.g., associated with a dashboard, a control panel, apedal, or a lever of a vehicle), a display, a keypad, a keyboard, apointing device (e.g., an electronic mouse) or another device forentering data (e.g., mode selection data) into the controller 75. In oneembodiment, the user interface 77 supports a user entering in controldata to select an operational mode (e.g., parallel hybrid operationalmode or a series hybrid operational mode) for the control system 11. Thedriver 76 may generate suitable control signals or control data forcontrolling the states of each clutch assembly. The electrical output ofa generator 10 may be connected or coupled to an electrical storagedevice 81 (e.g., a battery), a drive motor 79, or another electricalload. As shown in FIG. 1, the generator 10 provides electrical energy toan energy storage device 81, which in turn is coupled to a drive motor79 for propelling a vehicle.

In one embodiment, each clutch assembly (16, 26, and 34) comprises anelectromagnetic clutch that has a stationary electromagnet, a rotor, andan armature. In one embodiment, the armature is composed of iron, steel,or another ferrous alloy or structure. The stationary electromagnet maybe formed by one or more windings, with or without a ferrous (e.g.,iron) core. During an active state of a clutch assembly, electricalenergy (e.g., electrical current) is applied to the electromagnet whichmagnetizes the rotor and magnetically attracts the armature axiallytoward the rotor such that the armature and rotor contact each other ata friction interface for generally synchronous rotation together. Duringan inactive state, electrical energy is withdrawn from the electromagnetsuch that a spring or magnetic bias of a permanent magnet may return thearmature to a rest state spaced apart from the rotor by an axial airgap. The rotor is associated with an input member, and the armature isassociated with an output member, or vice versa. In one configuration,each input member or output member may comprise a hub or other couplingmember adapted to receive a shaft, for instance.

In one embodiment, the first clutch assembly 16 may comprise anelectromagnetic clutch that has first input member 13 and a first outputmember 14. The first clutch assembly 16 has an active state in whichrotational energy is transmitted (or transferred) between the firstinput member 13 and the first output member 14 and an inactive state inwhich rotational energy is not transmitted between the first inputmember 13 and the first output member 14. As illustrated in FIG. 1, thefirst input member 13 is connected to the first cylindrical member 20and the first output member 14 is coupled to the generator shaft 12.Accordingly, during the active state rotational energy is transmittedbetween the first cylindrical member 20 and the generator shaft 12.

In one embodiment, the second clutch assembly 34 may comprise anelectromagnetic clutch that has a second input member 48 and a secondoutput member 46. The second clutch assembly 34 has an active state inwhich rotational energy is transmitted between the second input member48 and the second output member 46 and an inactive state in whichrotational energy is not transmitted between the second input member 48and the second output member 46. As illustrated in FIG. 1, the secondinput member 48 is coupled to the third cylindrical member 38 and thesecond output member 46 is coupled to a second cylindrical member 36 ora transmission shaft 42. Accordingly, during the active state rotationalenergy is transmitted between the third cylindrical member 38 and thetransmission shaft 42.

In one embodiment, the third clutch assembly 26 may comprise anelectromagnetic clutch that has a third input member 18 and a thirdoutput member 32. The third clutch assembly 26 has an active state inwhich rotational energy is transmitted between the third input member 18and the third output member 32 and an inactive state in which rotationalenergy is not transmitted between the third input member 18 and thethird output member 32. As illustrated in FIG. 1, the third input member18 is coupled to the engine shaft 24 and the third output member 32 ofthe third clutch assembly 26 is mechanically coupled to the second inputmember 48 (of the second clutch assembly 34) or the third cylindricalmember 38. Accordingly, during the active state rotational energy istransmitted between the engine shaft 24 and the third output member 32or the third cylindrical member 38.

The controller 75 may support operation of the control system 11 or itscomponents, in one or more of the following modes: a series hybrid mode,a parallel hybrid mode, a stationary power generation mode, aconventional internal combustion engine mode, or any other modedescribed herein. The controller 75 may comprise a driver 76 thatprovides a suitable control signal for energizing an electromagnet ofone or more clutch assemblies (16, 34, and 26). In an alternativeembodiment, the driver may provide a digital control signal or analogcontrol signal to the one or more clutch assemblies (16, 34, and 26)equipped with a control circuitry.

A first operational mode means an operational mode in which the engine28 supplies rotational energy to the generator 10 for power generation(i.e., electrical energy generation or alternating current or directcurrent power) where the controller generates control signals such thatthe first clutch assembly 16 is active, the second clutch assembly 34 isinactive, and the third clutch assembly 26 is active. The firstoperational mode may support a series hybrid operation or stationarypower generation for application to an external electrical load.

A second operational mode means an operational mode in which the engine28 supplies rotational energy to the transmission 30 where thecontroller 75 generates control signals such that the first clutchassembly 16 is inactive, the second clutch assembly 34 is active, andthe third clutch assembly 26 is active. The second mode may represent aconventional internal combustion engine mode without generatoroperation.

A third operational mode means an operational mode in which propulsionmay be provided by rotational energy from the engine 28 and byrotational energy from a motor coupled to the generator 10 where thecontroller generates control signals such that the first clutch assembly16 is active, the second clutch assembly 34 is active, and the thirdclutch assembly 26 is active. The third operational mode represents aparallel hybrid mode.

In the configuration of FIG. 1, the first input member 13 is connectedto a first cylindrical member 20 (e.g., first pulley); the second outputmember 46 is connected to a second cylindrical member 36 (e.g., a secondpulley) or coupled to transmission shaft 42; and the third output member32 is connected to a third cylindrical member 38 (e.g., a third pulley).Further, a first tension member 22 (e.g., first belt) engages the firstcylindrical member 20 (e.g., first pulley) and the third cylindricalmember 38 (e.g., third pulley) to facilitate simultaneous rotation ofthe first cylindrical member 20 and the third cylindrical member 38; asecond tension member 40 (e.g., second belt) engages the secondcylindrical member 36 (e.g., second pulley) and the fourth cylindricalmember 44 (e.g., fourth pulley) to support simultaneous rotation of thethird pulley and the fourth pulley.

The cylindrical members (20, 38, 36, and 44) may comprise pulleys,gears, sprockets, cogged wheels, or otherwise. The first tension member22 may comprise a belt, a cogged belt, a chain or a cable. Similarly,the second tension member 40 may comprise belt, a cogged belt, a chainor a cable. If the cylindrical members (20, 38, 36, and 44) comprisegears or sprockets; the tension members may comprise chains thatrotationally couple the first cylindrical member 20 to the thirdcylindrical member 38 and rotationally couple the second cylindricalmember 36 to the fourth cylindrical member 44 (or the transmission shaft42).

The control system 111 of FIG. 2 is generally similar to the controlsystem 11 of FIG. 1, except the control system 111 of FIG. 2 replacesthe pulleys and belts combinations or chain and sprocket combinations ofFIG. 1 with gear assemblies (205, 207). Each gear assembly comprises thecombination of two engaging gears.

In FIG. 2, the first cylindrical member comprises a first gear 201; thethird cylindrical member comprises a third gear 202; the secondcylindrical member comprises a second gear 203; and the fourthcylindrical member comprises fourth gear 204. The first gear 201 engagesthe third gear 202 for mutual rotation therewith. The second gear 203engages a fourth gear 204 (or transmission gear, which is associatedwith the transmission shaft 42) for mutual rotation therewith.

In an alternate embodiment, the first clutch assembly 16, the secondclutch assembly 34, and the third clutch assembly 26, and the first gear201, second gear 203, third gear 202, and fourth gear 204 are arrangedto form mode control gearbox 31. For example, the mode control gearbox31 and the transmission 30 may be combined in an integral housing 33.

The control system 211 of FIG. 3 is generally similar to the controlsystem 11 of FIG. 1, except the second clutch assembly 34 is coupled toa transmission shaft 42, instead of the third cylindrical member 38 orthe third clutch assembly 26. Further, in the configuration of FIG. 3,the second input member 48 of the second clutch assembly 34 is connectedto the fourth cylindrical member 44 and the second cylindrical member 36is coupled or connected to the third cylindrical member 38. In both FIG.1 and FIG. 3, the second clutch assembly 34 couples or decouples theengine shaft 24 to the transmission shaft 42. In other words, the secondclutch assembly 34 determines whether or not rotational energy istransmitted between the engine shaft 24 and the transmission shaft 42.In FIG. 3, if the second clutch assembly 34 is in an inactive state, thefourth cylindrical member 44 (e.g., fourth pulley) may rotate freelywithout conveying rotational energy to the transmission input shaft 42.

The control system 311 of FIG. 4 is generally similar to the controlsystem 211 of FIG. 3, except the control system 211 of FIG. 4 replacesthe pulleys and belt combinations or chain and sprocket combinations ofFIG. 3 with gear assemblies.

Each gear assembly comprises the combination of two engaging gears. InFIG. 4, the first cylindrical member comprises a first gear 201; thethird cylindrical member comprises a third gear 202; the secondcylindrical member comprises a second gear 203; and the fourthcylindrical member comprises a fourth gear 204. The first gear 201engages the third gear 202 for mutual rotation therewith. The secondgear 203 engages the fourth gear 204 (or transmission gear, which isassociated with the transmission shaft 42) for mutual rotationtherewith.

In an alternate embodiment, the first clutch assembly 16, the secondclutch assembly 34, and the third clutch assembly 26, and the first gear201, second gear 203, third gear 202, and fourth gear 204 are arrangedto form a mode control gearbox. For example, the mode control gearboxand the transmission 30 may be combined in an integral housing (notshown).

FIG. 5 describes a method for controlling a vehicle. The method of FIG.5 begins in step S500.

In step S500, a controller 75 or operator selects an operational mode ofthe vehicle. The method of step S500 may be carried out in accordancewith various techniques, that may be applied separately or cumulatively.Under a first technique, the operator may operate a user interface, aswitch, a pedal-operated switch, a keyboard, a keypad, a pointing device(e.g., an electronic mouse) to select a mode of operation, such as aparallel hybrid mode, a series hybrid mode, a stationary powergeneration mode, a conventional internal combustion mode, or anotheroperational mode.

In step S502, a first clutch assembly 16 associated with a generator 10is provided, a second clutch assembly 34 associated with a transmission30 is provided, and a third clutch assembly 26 associated with an engine28 of the vehicle is provided. For example, the a first input shaft 14of the first cutch assembly 16 may be connected to a generator shaft 12of the generator 10; a second output member 46 of the second clutchassembly 34 is coupled to the transmission shaft 42; and the third inputmember 18 of the third clutch assembly is coupled to the engine shaft24, consistent with FIG. 1.

In step S504, the controller 75 controls the states of the first clutchassembly 16, the second clutch assembly 34, and the third clutchassembly 26 to achieve the selected operational mode. In a firstexample, the selected operational mode comprises a first operationalmode (e.g., series hybrid mode or stationary power generation mode) inwhich the engine 28 supplies rotational energy to the generator 10 forpower generation, and wherein the controlling comprises generatingcontrol signals such that the first clutch assembly 16 is active, thesecond clutch assembly 34 is inactive, and the third clutch assembly 26is active. In the first operational mode, the vehicle may be propelledby one or more drive motors 79 that are fed directly or indirectly fromthe electrical energy generated by the generator 10. In a secondexample, the selected operational mode comprises a second operationalmode (e.g., conventional internal combustion engine mode) in which theengine 28 supplies rotational energy to the transmission 30, wherein thecontrolling comprises generating control signals such that the firstclutch assembly 16 is inactive, the second clutch assembly 34 is active,and the third clutch assembly 26 is active. In an alternative version ofthe second operational mode, the first clutch assembly 16 may be active(or may vary between an active and inactive state) such that a generatorrecharges an electrical storage device 81. In a third example, theselected operational mode comprises a third operational mode (e.g.,parallel hybrid mode) in which propulsion may be provided by rotationalenergy from the engine 28 and by rotational energy from a motor coupledto the generator 10, and wherein the controlling comprises generatingcontrol signals such that the first clutch assembly 16 is active, thesecond clutch assembly 34 is active, and the third clutch assembly 26 isactive.

Having described the preferred embodiment, it will become apparent thatvarious modifications can be made without departing from the scope ofthe invention as defined in the accompanying claims.

1. A control system for a vehicle, the system comprising: a first clutchassembly comprising a first input member and a first output member, thefirst clutch assembly having an active state in which rotational energyis transmitted between the first input member and the first outputmember and an inactive state in which rotational energy is nottransmitted between the first input member and the first output member;a generator having a generator shaft, the generator shaft coupled to thefirst output member of the first clutch assembly; a second clutchassembly comprising a second input member and a second output member,the second clutch assembly having an active state in which rotationalenergy is transmitted between the second input member and the secondoutput member and an inactive state in which rotational energy is nottransmitted between the second input member and the second outputmember; a transmission having a transmission shaft coupled to the secondoutput member of the second clutch assembly; a third clutch assemblycomprising a third input member and a third output member, the thirdclutch assembly having an active state in which rotational energy istransmitted between the third input member and the third output memberand an inactive state in which rotational energy is not transmittedbetween the third input member and the third output member, wherein thefirst input member is connected to a first gear, the second outputmember is connected to a second gear, and the third output member isconnected to a third gear; the first gear engaging the third gear, thesecond gear engaging a fourth gear, wherein the fourth gear isassociated with the transmission shaft; an engine having an engine shaftcoupled to the third input member of the third clutch assembly; acontroller for establishing an operational mode of the vehicle bycontrolling the states of the first clutch assembly, the second clutchassembly, and the third clutch assembly using control data, wherein thecontrol data is provided by a driver to at least one of the first clutchassembly, the second clutch assembly, and the third clutch assembly, andwherein the control data is one of a digital control signal and ananalog control signal; and a user interface coupled to the controller,wherein the user interface receives the control data to select theoperational mode.
 2. The vehicle according to claim 1 wherein the firstinput member is connected to a first cylindrical member, the secondoutput member is connected to a second cylindrical member, and the thirdoutput member is coupled to a third cylindrical member; and furthercomprising a tension member for rotational coupling the firstcylindrical member to the third cylindrical member and for rotationalcoupling the second cylindrical member to the at least one of a fourthcylindrical member and the transmission shaft.
 3. The vehicle accordingto claim 1 wherein the first clutch assembly, the second clutchassembly, and the third clutch assembly, and the first gear, secondgear, third gear, and fourth gear are arranged to form a mode controlgearbox.
 4. The vehicle according to claim 3 wherein the mode controlgearbox and the transmission are combined in an integral housing.
 5. Thevehicle according to claim 1 wherein the first input member is connectedto a first sprocket, the second output member is connected to a secondsprocket, and the third output member is connected to a third sprocket;and further comprising chains for rotational coupling the first sprocketto the third sprocket and for rotational coupling the second sprocket toat least one of a fourth sprocket and the transmission shaft.
 6. Thevehicle according to claim 1 wherein the operational mode comprises afirst operational mode in which the engine supplies rotational energy tothe generator for power generation where the controller generatescontrol signals such that the first clutch assembly is active, thesecond clutch assembly is inactive, and the third clutch assembly isactive.
 7. The vehicle according to claim 1 wherein the operational modecomprises a second operational mode in which the engine suppliesrotational energy to the transmission where the controller generatescontrol signals such that the first clutch assembly is inactive, thesecond clutch assembly is active, and the third clutch assembly isactive.
 8. The vehicle according to claim 1 wherein the operational modecomprises a third operational mode in which propulsion may be providedby rotational energy from the engine and by rotational energy from amotor coupled to the generator where the controller generates controlsignals such that the first clutch assembly is active, the second clutchassembly is active, and the third clutch assembly is active.
 9. Thevehicle according to claim 1 wherein the first clutch assembly, thesecond clutch assembly, and the third clutch assembly compriseelectromagnetic clutches.